NATO Secretary-General Javier Solana told BBC-TV that the Serbian offensive was a "clear violation" of a cease-fire agreed to in October by Yugoslav President Slobodan Milosevic to end eight months of fighting and avoid NATO airstrikes.

At least one person was killed, and ethnic Albanians said several others were injured in what they said was an assault on six villages outside the town of Podujevo by Serbian police and troops backed with tanks.

Serbian police, quoted by the government's Tanjug news agency, said the operation was continuing Thursday night.